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991.
OBJECTIVE: To apply polymerase chain reaction (PCR) analysis to the fine needle aspiration biopsy (FNAB) evaluation of lymphoid proliferations. STUDY DESIGN: We analyzed 37 consecutive archived FNAB malignant lymphoma specimens. Immunophenotypic data from the fine needle aspiration biopsy and excisional biopsy material was available for all specimens. PCR to identify monoclonal rearrangements of the immunoglobulin heavy chain gene, T-cell receptor and translocations involving the bcl-1 and bcl-2 genes was performed. RESULTS: Seventy-eight percent of cases were detected by at least one of these assays. Where DNA analysis was performed on excisional biopsy material, 70% of the cases had identical results; no discordant results for the immunoglobulin heavy chain gene or T-cell receptor were found. In 23% of cases, after review of all available data, a discordant result was thought to be a consequence of a false negative result in DNA analysis of excisional biopsy material. CONCLUSION: These findings indicate that PCR analysis of archived FNAB material, when necessary, provides useful information for diagnosis and staging of malignant non-Hodgkin's lymphomas. 相似文献
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A group of schwannomas with interstitial deletions on 22q located outside the NF2 locus shows no detectable mutations in the NF2 gene 总被引:3,自引:0,他引:3
Carl E. G. Bruder Koichi Ichimura O. Tingby Kimiyoshi Hirakawa Atsushi Komatsuzaki Akira Tamura Yasuhito Yuasa V. Peter Collins J. P. Dumanski 《Human genetics》1999,104(5):418-424
Schwannomas are tumors arising mainly at cranial and spinal nerves. Bilateral vestibular schwannoma is the hallmark of neurofibromatosis
type 2 (NF2). The NF2 gene has been cloned and comprehensive analysis of its mutations in schwannomas shows that up to 60% of tumors carry inactivating
mutations. Thus, the genetic mechanism behind the development of more than 40% of schwannomas without NF2 mutations is unknown. We have therefore studied tumor tissue from 50 human schwannomas by allelotyping and have found chromosome
22 deletions in over 80% of the cases. We detected 14 cases (27%) that revealed partial deletions of one copy of chromosome
22, i.e., terminal and/or interstitial deletions. We sequenced the NF2 gene in seven of these tumors and detected only one case with mutations. The deletion mapping of chromosome 22 in tumors
with partial deletions indicates that several regions, in addition to the NF2 locus, harbor genes involved in schwannoma tumorigenesis. Our findings suggest that heterogeneity in the mechanisms leading
to the development of schwannomas probably exists. These findings are in agreement with the recent analysis of schwannomas
from familial and sporadic cases of schwannomatosis and point to a possible role of an additional gene, which, in cooperation
with the NF2 tumor suppressor, causes schwannomas.
Received: 12 November 1998 / Accepted: 1 March 1999 相似文献
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996.
J S Sullivan C L Morris B B Richardson G G Galland V M Jennings J Kendall W E Collins 《The Journal of parasitology》1999,85(4):672-677
A chloroquine-resistant strain of Plasmodium vivax (AMRU-1) from Papua New Guinea has been adapted to grow in 4 species of Aotus monkeys (Aotus lemurinus griseimembra, Aotus vaciferans, Aotus nancymai, and Aotus azarae boliviensis), hybrid Aotus monkeys, and Saimiri boliviensis monkeys. Whereas it was possible to infect Saimiri monkeys with this parasite by inoculation of parasitized erythrocytes, only 42% of Saimiri monkeys became infected, compared to 92% of Aotus monkeys attempted. Comparative mosquito feedings showed that only A. vociferans, A. l. griseimembra, and Saimiri boliviensis monkeys produced infections in mosquitoes. Oocysts were observed on the guts of the 4 species of mosquitoes used (Anopheles gambiae, Anopheles stephensi, Anopheles freeborni, and Anopheles dirus), but sporozoite transmission was effected only with the intravenous inoculation of sporozoites from An. dirus into an A. l. griseimembra monkey. 相似文献
997.
Group D Adenoviruses Infect Primary Central Nervous System Cells More Efficiently than Those from Group C 总被引:3,自引:2,他引:1 下载免费PDF全文
Miguel Chillon Assumpci Bosch Joseph Zabner Lane Law Donna Armentano Michael J. Welsh Beverly L. Davidson 《Journal of virology》1999,73(3):2537-2540
Group C adenovirus-mediated gene transfer to central nervous system cells is inefficient. We found that wild-type group D viruses, or recombinant adenovirus type 2 (Ad2) (group C) modified to contain Ad17 (group D) fiber, were more efficient in infecting primary cultures of neurons. Together with studies on primary vascular endothelial cells and tissue culture cell lines, our results indicate that there is not a universally applicable adenovirus serotype for use as a gene transfer vector. 相似文献
998.
Amy S. Kennedy Emma L. Carroll Alexandre N. Zerbini C. Scott Baker Manuela Bassoi Nazarena A. Beretta Danielle L. Buss Susannah Calderan Ted Cheeseman Martin A. Collins Paula Costa-Urrutia Paul Ensor Karina Groch Russell Leaper Paula Olson Cecilia Passadore Federico G. Riet-Sapriza Els Vermeulen Florencia Vilches Andrew G. Wood Jennifer A. Jackson 《Marine Mammal Science》2024,40(2):e13089
The sub-Antarctic waters of South Georgia Island (Islas Georgias del Sur, SG/IG) are a regularly visited feeding ground for southern right whales (Eubalaena australis, SRW) in the southwest Atlantic. Satellite telemetry and photo-identification records were compared to better understand the role of SG/IG in the SRW migratory network. We present the first insights from SRW satellite-tracked from the SG/IG feeding ground, habitat use patterns in the Scotia Arc, and movements to Antarctic habitats. Photo-identification comparisons to calving and feeding areas across the South Atlantic and a review of sightings of cetaceans reported from Bird Island (west of SG/IG) since 1979 illuminate long-term habitat use patterns in SG/IG. We present the first recorded migratory movement between SG/IG and multiple countries: Argentina, Uruguay, and Brazil. Photo-identification (1) linked SG/IG to a female SRW with a long-term sighting history in Brazil, and (2) provided the first match between SG/IG and the western Antarctic Peninsula, suggesting the latter could extend the feeding area for southwest Atlantic SRW. Satellite tracking and opportunistic sightings suggest that shelf and coastal waters west of SG/IG represent an important multi-season SRW feeding habitat and add to our overall understanding of habitats and ranges occupied by recovering southwest Atlantic SRW. 相似文献
999.
The distinction prevalent in the social sciences between the terms sex and gender is a useful one and ought to be preserved. Sex refers to the anatomical or chromosomal categories of male and female. Gender refers to socially constructed roles that are related to sex distinctions. Use of these terms as synonyms is becoming increasingly frequent in physical anthropology, especially among bioarchaeologists and primatologists. A failure to make the distinction between gender and sex is analytically incapacitating in a field such as physical anthropology, whose strength lies in the integration of biological and cultural information. Am J Phys Anthropol 106:255–259, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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